Background
Approximately 60% to 80% of patients with congenital central hypothyroidism (CH-C) have multiple pituitary hormone deficiencies (MPHDs), making CH-C a potentially life-threatening disease. However, data on childhood mortality in patients with CH-C are lacking.

Objectives
To study the mortality rate in pediatric patients with early-detected and treated CH-C in the Netherlands and to investigate whether causes of death were related to pituitary hormone deficiencies.

Methods
Overall mortality rate, infant mortality rate (IMR) and under-5 mortality rate were calculated in all children with CH-C detected by neonatal screening between 1 January 1995 and 1 January 2013. Infant and under-5 mortality rates among children with CH-C were compared to mortality rates in the Netherlands in the same time period as registered by Statistics Netherlands (CBS). Medical charts were reviewed to establish causes of death.

Results
A total of 139 children with CH-C were identified, of which 138 could be traced (82 with MPHD, 56 with isolated CH-C). Total observation time was 1414 years with a median follow-up duration of 10.2 years. The overall mortality rate was 10.9% (15/138). IMR and under-5 mortality rate were 65.2/1000 (9/138) and 101.4/1000 (14/138), respectively, compared with an IMR of 4.7/1000 and under-5 mortality of 5.4/1000 live-born children in the Netherlands during the same time period (p < 0.0001). Main causes of death were severe congenital malformations in six patients, asphyxia in two patients, and congenital or early neonatal infection in two patients. Pituitary hormone deficiency was noted as cause of death in only one infant.

Conclusion
We report an increased mortality rate in patients with early-detected CH-C that does not seem to be related to endocrine disease. This suggests that mortality due to pituitary insufficiency is low in patients with early-detected and early-treated CH-C.